Domain Name Server (DNS), in general, refers to a service or a server that translates a domain name, such as, a website name or a Uniform Resource Locator (URL) into an Internet Protocol (IP) address. The IP address may be an identifier of a node (computing device), in particular, a host, within a network of nodes and may be utilized for communication between the host and other nodes within the network. The host, as identified by the IP address, may store content associated with the website name or the URL and may provide the content to the DNS and/or a client device of a user that requested the domain name. For translating the domain name into the IP address, the DNS may utilize mapping information that generally includes records of most frequently requested domain names with their respective IP addresses.
On some instances, the DNS may not be able to translate the domain name to the corresponding IP address, due to reasons, such as unavailability of the mapping information for the domain name. The DNS, on such occasions, may request another DNS, often referred to as a backend server or an authoritative server, to provide the corresponding IP address. The backend server, upon receiving the request, may search for the corresponding IP address within mapping information stored in the cache (or database) of the backend server and provide the corresponding IP address to the DNS. A host may then be identified based on the IP address for retrieving content associated with the domain name and providing the content to the client device.